Teenage Engineering is branching out into instrument amps with the previously leaked EP-35, a multi-input, multi-instrument, battery-powered amp with built-in effects. The back of the unit has a line-in port, as well as a 1/4-inch guitar input and an XLR input for mics, including mics that require phantom power. You can also stream audio to it via Bluetooth and connect multiple EP-35s together over Bluetooth using Auracast. If you have them paired in stereo, tilting a unit to the left or right sets it to the appropriate stereo channel, which is pretty neat.
There are separate effects processors for guitar and vocals, though you have limited options for each.